Get proc SQL to produce 95% confidence interval

I created SAS code using proc SQL to calculate a weighted mean by year. My SAS code is below. My weight variable is called bwght and I weight the variable called CPUE for each year. This code produces the weighted mean by year and calls it bwghtedAverage. However, I can't figure out how I an get proc sql to also provide me with the 95% confidence intervals for this mean. Any help would be greatly appreciated.